Alpha-sorting multiple rows, empty cells for missing values

Say I have multiple columns:

A    | B    | C…Bill | Bill | JohnAdam | Fran | Nick     | Adam2| Adam

I’d like to alpha sort the rows in each column, and also add empty values in a cell if the cell does not have the same value as its row-sibling cells. The result would look like:

A    | B     | C…Adam |       | Adam     | Adam2 |Bill | Bill  |      | Fran  |     |       | John     |       | Nick